Shutdown - Siemens RVW26.000B27 Basic Documentation

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Siemens Building Technologies
HVAC Products

5.4 Shutdown

Burner control
Burner control is in its
operating position
If the start control loop opens,
the shutdown sequence is
started.
The fuel valves will shut down
Starts the postpurge time if
required
Switches the fan motor off
Controls the actuators
= display of burner output on the RVW26...
n
Note:
The RVW26... identifies the burner control's startup and shutdown sequence from the
control commands.
This control sequence takes place according to a fixed basic pattern (burner control
program).
Departures from this basic pattern will not be accepted by the RVW26... and lead to
lockout.
Do not include contactor or relay contacts in the signal lines!
If this is not possible, make certain that such contacts – due to delayed signals – do not
adversely affect the correct functioning of the unit
Electronic Air / Fuel Ratio Control System
5 Description of functions
RVW25
LR
X1
LR
TxD
RxD
BV1
G
LKZ
+ RVW25
QUIT
Q1 = 230 V
RVW26
RVW26... is in its operating
U1
position
RxD
TxD
Identifies burner shutdown.
Q2
Responds no longer to load
positioning signals.
Sets Q1 = 0 V
Q3
Closes all actuators
Y20
When all actuators are closed,
Q1 = AC 230 V indicates
Q1 readiness to make a new start
.
Display
.
-8.-
-9.-
-0.-
CC1P7873.1en
15.10.2002